Hi Laurent,
On Wed, Feb 20, 2019 at 02:51:22PM +0200, Laurent Pinchart wrote:
> Signed-off-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
> ---
> yavta.c | 25 +++++++++++++++++++++++++
> 1 file changed, 25 insertions(+)
>
> diff --git a/yavta.c b/yavta.c
> index 1490878c6f7e..2d49131a4271 100644
> --- a/yavta.c
> +++ b/yavta.c
> @@ -1334,6 +1334,31 @@ static int video_parse_control_array(const struct v4l2_query_ext_ctrl *query,
> __u32 value;
>
> for ( ; isspace(*val); ++val) { };
> +
> + if (*val == '<') {
> + /* Read the control value from the given file. */
> + ssize_t size;
> + int fd;
> +
> + val++;
> + fd = open(val, O_RDONLY);
> + if (fd < 0) {
> + printf("unable to open control file `%s'\n", val);
> + return -EINVAL;
> + }
> +
> + size = read(fd, ctrl->ptr, ctrl->size);
Note that a read of count reads *up to* count number of bytes from the file
descriptor. In other words, it's perfectly correct for it to read less than
requested.
How about using fread(3) instead? Or changing this into a loop?
> + if (size != (ssize_t)ctrl->size) {
> + printf("error reading control file `%s' (%s)\n", val,
> + strerror(errno));
> + close(fd);
> + return -EINVAL;
> + }
> +
> + close(fd);
> + return 0;
> + }
> +
> if (*val++ != '{')
> return -EINVAL;
>
--
Regards,
Sakari Ailus
